/*
 * Copyright 2014 the original author or authors.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.xd.samples;

import java.util.ArrayList;
import java.util.List;

import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.xd.tuple.Tuple;
import org.springframework.xd.tuple.TupleBuilder;

/**
 * @author David Turanski
 */
class ProductCategoryEnricher {
	private final RedisTemplate<String, String> redisTemplate;

	public ProductCategoryEnricher(RedisTemplate<String, String> redisTemplate) {
		this.redisTemplate = redisTemplate;
	}

	String getCategory(String productId) {
		String content = redisTemplate.boundValueOps(productId).get();
		Tuple product = TupleBuilder.fromString(content);
		return product.getString("category");
	}

	public Tuple enrichEvent(Tuple event) {
		if ("PRODUCT".equals(event.getString("type"))) {
			List<String> names = new ArrayList<>(event.getFieldNames());
			List<Object> values = new ArrayList(event.getValues());
			names.add("category");
			values.add(getCategory(event.getString("product")));
			return TupleBuilder.tuple().ofNamesAndValues(names, values);
		}
		else {
			return null;
		}
	}
}